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[mkgmap-dev] MDR success and a couple of questions

From Steve Ratcliffe steve at parabola.me.uk on Wed Sep 30 00:18:35 BST 2009

Hi Alex

> The unknown byte is sequential as you see above.
>> From MDR4 where the type changes(just type, no the subtype) it
> coresponds to a record here.
> So you have a type from here you find where point with that type start in MDR10.

At first I didn't see how this could work with my example files, but I
now think you are correct with one small difference in that type 0x28
is out of place:

first byte: type
1: all city types and perhaps all indexed points
2: 2a
3: 2b
... etc
7: 2f
8: 30
9: 28

So group 9 is out of order. Also what about points that have a type >
0x30?  File that have such points do not any entries in mdr 4 for
them. Perhaps you just can't search for them?

> MDR10 - POIs indexed by type
> 1 bytes - subtype
Ha - I realised today it was subtype and not type, but I see you
said it first.

> 2/3 bytes - POI index in MDR11 - index have 0x8000 or 0x800000 flag->
> if the point is indexed or not

I think this flag is actually to say if the name is new or not.  If
the flag is not set, then the name of the POI is the same as the
name of the previous poi.

Thanks I think I will be able to write mdr9 tommorow and hopefully 
everything will stop being a city!



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